High Lockout
Indicator: Reset/Standby lit on Glow-worm Hideaway 80

Your boiler has switched itself off because it has either gotten too hot or it failed to light the flame correctly.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

Check water system for overheating or ignition failure

What causes this fault?

This fault happens when either the boiler’s internal temperature has exceeded safe limits or the burner has failed to light after several attempts. It is often triggered by a lack of water flow preventing heat from leaving the boiler, or an issue with the electrical spark that starts the flame.

This issue often appears during the first cold snap of autumn when a pump that has been sitting idle all summer fails to start up.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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